Expansible mandrel



AIN. G. NAccARA 3,391,878

EXPANS IBLE MANDREL July 9, 1968 2 Sheets-Sheet 1 Filed April 25, 1967INVENTOR: NRCHOLAS G7 NACCARA ATTORNEY July 9, 1968 N. G. NACCARAEXPANSIBLE MANDREL 2 Sheets-Sheet 2 Filed April 25, 1967 INVENTOR:

NICHOLAS G. NACCARA ATTORNEY United States Patent O 3,391,878 EXPANSIBLEMANDREL Nicholas G. Naccara, Hewitt, NJ., assignor to Cameron MachineCompany, Dover, NJ., a corporation of New York Filed Apr. 2S, 1967, Ser.No. 634,433 4 Claims. (Cl. 242-72) ABSTRACT OF THE DISCLOSURE Pluralbuttons, extending radially outwardly through holes in a cylindricalshell to provide an expansion effect, are urged outwardly by aninflatable tube which is part of a readily insertable and removable unitincluding also end, tube carriers and an internal tube support. The endsof the tube are secured fluid-tightly between threaded outer surfaces ofthe tube carriers which engage the inside of the tube, and annulartooth-like ridges of inner surfaces of tube retaining sleeves whichengage the outside of the tube.

Background of the invention and prior art Expansible mandrels arecommonly employed in machines for winding and unwinding rolls of webmaterial, the mandrel being expanded in a roll core (not shown) totightly engage the Core internally. Upon completion of a winding orunwinding operation, contraction of the mandrel permits its removal fromthe core. Satisfactory means have not hitherto been developed forproviding such a readily insertable and removable tube unit; and meanshitherto provided for supporting and closing the ends of such aninflatable tube have not been entirely satisfactory. Additionally, priorexpansible mandrels employing springs for retraction of the buttons havenot provided for external removal of both the buttons and the springs tofacilitate servicing. Also, the prior art provides no satisfactory meansfor readily converting a button type of expansible mandrel to a leaftype having relatively broad outer leaves which are movable radiallyoutwardly to increase the effective diameter of the mandrel.

Summary of the invention An assembly of an inflatable tube, for pressingbuttons outwardly to expand the mandrel, tube carrying members connectedto Opposite ends of the tube, one of said members having an air passageto permit ination of the tube, and a rigid, internal tube support,engaging both said members, constitute a unit which is readilyinsertable into and removable from a rigid cylindrical shell tofacilitate assembly and service of the mandrel. Both the buttons andsprings for retracting the buttons are accessible from the exterior ofthe mandrel for removal for servicing, and the buttons are adaptable toreceive outer leaves as expanding parts of the mandrel. The inventionalso includes an arrangement wherein the opposite ends of the tube aresecured fluid-tightly between threaded portions of the tube carryingmembers extending within the tube and annular tooth-like ridges of innersurfaces of tube retaining sleeves which engage the outside of the tube.

Brief description of the drawing ln the accompanying drawing, employedwithout limitation as illustrative of this invention:

FIG. l is a central longitudinal sectional view of a preferred form ofexpansible mandrel according to this invention;

FIG. 2 is a transverse sectional view substantially on the line 2 2 ofFIG. l; the parts being as when the man drel is in normal ornon-expanded condition;

,39L873 Patented July 9, 1968 ice FIG. 3 is a View at the same line asin FIG. 2; the parts, however, being as when the mandrel is in expandedcondition;

FIG. 4 is a transverse sectional view substantially on the line 4-4 ofFIG. l; the parts being as when the mandrel is in normal or non-expandedcondition;

FIG. 5 is a diagrammatic, perspective illustration of a leaf-typemodification employing relatively broad leaves as outer expandingmembers;

FIGS. 6 and 7 are transverse sectional views of the outer-leaf type ofmandrel shown in FIG. 5; these views, respectively, being somewhatsimilar in general character to FIGS. 2 and 4, except that, in FIG. 7,the mandrel appears as in expanded condition rather than in itsnonexpanded condition of FIG. 4.

Description of the preferred embodiments The first embodiment,illustrated in FIGS. 1 4, comprises a rigid, cylindrical shell 10,having journals 12 and 14 at its opposite ends, iixedly connected to theshell by set screws 16 and 18.

Within the shell 10 is a circular series of equally spaced, relativelyrigid, longitudinal inner leaves 20 of arcuate cross section, four suchleaves being shown in said series. These leaves may either be singlepieces, as illustrated, extending throughout the greater part of thedistance between the journals 12 and 14 or each may be of two or morepieces approximately equaling the length of such a single piece leaf.

The inner leaves 2% are sometimes hereinafter referred to as buttoncarriers, for plural buttons 22 are suitably fixed thereto at suitableplural points therealong and extend into button holes 24 formed, inradial register therewith, in the shell 19.

Within the circular series of button carriers 20 extends a unitaryassembly 25 of an iniiatable tube 26 of rubber or other suitableresilient material, tube carrying members 28 and 36 to inner portions ofwhich opposite ends of the tube are similarly air-tightly fixed by beingtightly squeezed between retaining sleeves 32 having inner, annulartooth-like ridges 32a embedded in the outer surface of the tube, andthreaded portions 28a and 30a of the members 28 and 3i) which arethreaded with a squeeze iit into the tube and into internally threadedportions 32h of sleeves 32 at the latters outer ends.

The apexes of ridges 32a are preferably directed toward the outerextremity of the adjacent end portion of the tube 26 to give greaterassurance against the ends of said tube becoming dislodged fromengagement Iwith the sleeves 32 and the threaded portions 28a and 30a ofthe members 23 and 36 when the tube is inated.

The assembly 25 also includes a relatively rigid supporting rodillustrated as a tube support 34, extending closely within the tube 26when the latter is in normal non-inflated condition, with the oppositeends 36 of said rod seated firmly within complemental recesses 38 formedin the inner ends of the tube carrying members 28 and 3i) to space thelatter precisely from each other. The tube support 34 also serves tooppose inward collapse of the tube Z6 upon deflation of the latter and,if the tube support 34 is solid :as illustrated, said support alsoenables the tube to be inflated rapidly by limiting the volume of airwhich may be introduced thereinto.

When the tube 26 is deflated and supported by the support 34, thebuttons 22 extend radially outwardly, substantially into the holes 24 tohold the button carriers 20 in their proper operating positions. Thebuttons are of such length that, upon radially outward movement of saidbutton carriers upon iniiation of the tube 26 as shown in FIG. 3, thebuttons extend beyond the outer surface of the shell 10, therebyincreasing the effective diameter of the mandrel.

Subsequent :deation of the tube 26 may enable the buttons 22 to recedeto their retracted positions as in FIG. 2, but it is preferred thatforceful button retracting means be provided. Such retracting means areshown as plural compressed coil springs 40, each seated at its inner endupon an outer surface of a related button carrier 2i), preferably withina `depression 42 formed in said button carrier, and held within arelated spring opening 44 -by `a peened-in plate or plug 46. A pluralityof such springs are provided for each button carrier 20, the springopenings 44 yand springs therein being suitably located in symmetricalrelation to that `,button carrier to apply button retraction force tothe latter substantially uniformly therealong.

Each button 22 comprises :a headed nut 48 (FIG. 2) having its shankextending outwardly into a hole 5t! in a related button carrier and acup-like body member 52 held with its lbottom against the outer end ofsaid nut by a stud bolt 54. The stud bolts head is within an outer endcup recess in the body member 52 and the bolts shank extends through ahole 56 in the bottom of the ybody member 52 and is threaded tightlyinto the nut 48. The stud bolt 54 is accessible from the exterior of themandrel to permit easy removal and replacement of the body 52 whennecessary.

The plugs 46 holding the springs 40 in place are removable forreplacement of springs as may be necessary by inserting a suitablepulling tool into a hole which may be drilled in :a plug, whereafter theplug m-ay be pulled from the shell 10 to permit spring removal andreplacement. It will be seen that the springs 40, as with the principalparts of the buttons 22, are readily removable for servicing from theexterior of the mandrel.

An air pipe 58, into which air may -be introduced through a releasablecheck valve 60 at the open end of journal 14, extends within a bore 62in the latter and 'is airtightly fixed at its inner end into alongitudinal bore 64 in the right, tube carrying member 30. The bore 64communicates with a cross-'bore 66 in the member 30 to carry air intothe rubber tube 26 to inate the latter.

When the tube 26 is inflated, the button carriers 20 and their relatedlbuttons 22 are forced radially outwardly to eifect expansion of themandrel, and the check valve 60 holds the air in the tube during theperiod of time in which expansion of the mandrel is to be maintained.Subsequent release of the valve 60 permits the tube to become ldetiated,thus permitting the button carriers and their related buttons to retractto restore the mandrel to its non-expanded condition. The springs 40serve as means operative directly upon the button carriers to affordgreater assurance of such button retraction.

Although the rigid tube support 34 is indicated as preferably Ibeing ofsolid plastic material, it may be of other rigid material and need notnecessarily be solid. Thus, it may be hollow, with an air-imperviouswall, in which arrangement it will function similarly to the disclosedsolid plastic arrangement. Moreover, if it is desired to employ agreater volume of air to inflate the rubber tube 26, the rigid tubesupport 34 may be hollow with its Wall perforated to permit =air to'iindits Way into said tube support; or the latter may be of rigidbutopen-cellular material.

In assembling the illustrated mandrel, the unitary assembly 25 iscompletely formed, independently of other parts of the mandrel, bysliding the tube support 34 into the rubber tube 26, and sliding theretaining sleeves 32 onto the opposite ends lof the tube. Then, the leftand right tube carrying members 28 and 30 are threaded into oppositeends of the rubber tube thereby seating the ends of the tube support 34in the recesses 38 of said members.

lEither before or after formation of the unitary assembly 25, the leftend (as illustrated) of the shell 10 is secured by set screws 16 (onlyone being shown) to the journal 12, and the button carriers 20, with the|buttons 22 Iaflixed thereto, are slid into the then open end of theshell and lare pushed and suitably held radially outwardly with thebuttons extending into related holes 24 in the shell.

Preferably at this point, the air pipe 58, with the valve thereon, isthreaded tightly into the end of the bore 64 in the member Sil,whereafter the right journal 14 is slid onto the outer end of the member30 and fixed thereon by set screws 68 (only one Ibeing shown).

Next, the entire, unified assembly 25, with the related journal 14 andthe air pipe 58, are pushed into the then open right end of the shell,interiorly of the button carriers 2t), until the left member 28 of theassembly firmly abuts the inner end of the journal 12, whereafter, withthe tube support 34 tightly held between members 28 and 30, the assemblyis locked into place in the shell by set screws 18 (only one beingshown).

The second embodiment, illustrated in FIGS. 5-7, differs from theabove-described first embodiment chieliy in the addition of elongate,external, expanding leaves 78 of arcuate shape in cross-section. FIG. 5diagrammatically discloses only the shell 10 and the leaves 70 to showclearly the relationship between those parts.

The leaves 70 are of such width that their side edges 72 come very closetogether when the mandrel is in contracted condition. Said leaves areconnected to the inner leaves 20 by countersink-headed bolts 74extending through countersunk holes 76 in the leaves 70', thence,through spacer sleeves 78 and into the headed nuts 48 into which theyare tightly threaded.

Under some conditions a user of the leaf type mandrel of the secondembodiment might wish to convert it to a button type mandrel or viceversa. Such a conversion is easily accomplished from the exterior of thedevice by removing the bolts 74, sleeves 78 and the leaves 70,substituting for them the member 52 and the bolt 54 of the firstembodiment.

As, with relatively slight changes in parts 52, 54 of FIG. 2 externalleaves 70 could be applied thereto and/ or with relatively slightchanges in parts 74, 78 of FIG. 6, those parts could be given thecharacter of buttons, it may properly be considered that the leaves 70are mounted upon series of buttons.

It will be realized that the mandrel of the second embodiment, much likethat of the lirst embodiment is easily serviced as to the externalleaves 70 andthe springs 40, without the necessity of removing either ofthe journals or any of the parts located within the shell 10.

Those familiar with the subject art will understand that the inventiveconcepts disclosed herein may be utilized in various other waysWithoutrdeparting from the invention as set forth in the followingclaims.

I claim:

1. In an expansible web-Winding mandrel having a rigid, cylindricalshell, journals fixed to opposite ends of the shell, plural, elongatebutton carriers arranged in a circular series within said shell, pluralbuttons fixed to said carriers and projecting radially outwardly intoseries of holes in said shell extending longitudinally of the latter,and expanding means within said series of button carriers for pressingsaid carriers radially outwardly to project portions of said buttonsoutwardly beyond the outer surface of said shell; the improvementcomprsing an arrangement in which said expanding means compirses aunitary assembly including an inflatable, resilient tube, tube carryingmembers fluid-tightly connected to opposite ends of said tube and heldconcentcally in engagement with inner end portions of said journals, anda rigid, elongate supporting rod Within said tube having end portions inend to end engagement with inner end portions of said tube carryingmembers; one of said members being formed with a lluid carrying passageopening into said tube and being accessible from the exterior of themandrel for injection of uid into the tube; the improvement furtherincluding plural coil springs coacting with said button carriers to urgethe latter radially inwardly, said springs being disposed within springholes in said shell with their inner ends bearing against related buttoncarriers, and said spring holes having plugs therein, removable from theexterior of the shell, and in retaining engagement with said springs atthe latters outer ends; and said buttons being adapted for removal fromthe mandrel from the exterior of the shell whereby to facilitateservicing with respect to both the buttons and the springs.

2. In an expansible web-winding mandrel having a rigid, cylindricalshell, journals fixed to opposite ends of the shell, plural, elongatebutton carriers arranged in a circular series Within said shell, pluralbuttons fixed to said carriers and projecting radially outwardly intoseries of holes in said shell extending longitudinally of the latter,and expanding means within said series of button carriers for pressingsaid carriers radially outwardly to project portions of said buttonsoutwardly beyond the outer surface of said shell; the improvementcomprising an arrangement in which said expanding means comprises aunitary assembly including an inflatable, resilient tube, tube carryingmembers fluid-tightly connected to opposite ends of said tube and heldconcentrically in engagement with inner end portions of said journals,and a rigid, elongate supporting rod within said tube having endportions in end to end engagement with inner end portions of said tubecarrying members; one of said members being formed with a uid carryingpassage opening into said tube and being -accessible from the exteriorof the mandrel for injection of iluid into the tube; said buttons sachcomprising a cuplike body member and a headed stud bolt extendingthrough a hole in the bottom of said body member with the bolts headWithin the body member and a threaded shank portion of the boltthreadedly connected to a related button carrier; the head of the boltbeing exteriorly accessible to permit removal of the bolt yand the bodymember from the exterior of the mandrel.

3. In an expansible web-winding mandrel having a rigid, cylindricalshell, journals iixed to opposite ends of the shell, plural, elongatebutton carriers arranged in a circular series within said shell, pluralbuttons fixed to said carriers and projecting radially outwardly intoseries of holes in said shell extending longitudinally of the latter,and expanding means within said series of button carriers for pressingsaid carriers radially outwardly to project portions of said buttonsoutwardly beyond the outer surface of said shell; the improvementcomprising an arrangement in which said expanding means comprises aunitary assembly including an inflatable, resilient tube, tube carryingmembers uid'tightly connected to opposite ends of said tube and heldconcentrically in engagement with inner end portions of said journals,and a rigid elongate supporting rod within said tube having end portionsin end to end engagement with inner end .portions of said tube carryingmembers; one of said members being formed with a fluid carrying passageopening into said tube and being accessible from th @exterior of themandrel for injection of iiuid into the tribe; said buttons eachcomprising a base member held to a related button carrier againstradially outward movement relatively thereto, a main button member, andmeans rigidly inter-connecting the two latter members; the mandrelfurther including a circular series of elongate, transversely arcuate,outer leaves and means for rigidly securing said outer leaves to saidbuttons.

4. In an expansible web-winding mandrel having a rigid, cylindricalshell, journals iixed to opposite ends of the shell, plural, elongatebutton carriers arranged in a circular series within said shell, pluralbuttons fixed to said carriers and projecting radially outwardly intoseries of holes in said shell extending longitudinally of the latter,and expanding means within said series of button carriers for pressingsaid carriers radially outwardly to project portions of said buttonsoutwardly beyond the outer surface of said shell; the improvementcomprising an arrangement in which said expanding means comprises aunitary assembly including an inatable, resilient tube, tube carryingmembers fluid-tightly connected to opposite ends of said tribe and heldconcentrically in engagement with inner end portions of said journals,and a rigid, elongate supporting rod Within said tube having endportions in end to end engagement with inner end portions of said tubecarrying members; one of said members being formed with a uid carryingpassage opening into said tube and being accessible from the exterior ofthe mandrel for injection of uid into the tube; the improvement furtherincluding similar connections for duid-tightly connecting said tubecarrying members to opposite ends of the tube; each of said connectionscomprising a rigid retaining sleeve having an internally threaded outerend portion and an inner end portion extending about an adjacent endportion of the tube and provided with an inner annular ridge ernbeddedin the outer surface ofthe tube, and the related tube carrying memberhaving an externally threaded portion, threaded through said threadedouter end portion of said sleeve and into the adjacent end portion ofthe tube into radial alignment with said ridge in position to squeezethe tubes said end portion between said ridge and said threaded portionofthe sleeve.

References Cited UNITED STATES PATENTS 2,797,474 7/ 1957 Main 29-5063,048,345 8/ 1962 Willard 242-72 3,127,124 3/l964 Tidland 242-72 FOREIGNPATENTS 1,042,372 10/ 195 S Germany.

FRANK I. COHEN, Primary Examiner.

NATHAN L. MINTZ, Examiner.

